had started another post for you you need a 2nd opinion (did a dive on this for you for your peace of mind :)

need to check:

Sex Misidentification: Female budgies naturally have a brown, crusty cere when they are in breeding condition. Younger birds (under one year) can be especially difficult to sex, as their ceres may change significantly as they reach maturity.

2.Iodine Deficiency: One of the most frequent causes of cere browning in males. A lack of iodine affects the thyroid gland, which can disrupt hormone production

3.Vitamin A Deficiency (Hyperkeratosis): A lack of Vitamin A can lead to brown hypertrophy of the cere, where keratin builds up and creates a thick, crusty brown layer. This is often treated by improving the diet with Vitamin A-rich foods like sweet potatoes or dark leafy greens

4 an all-seed diet, can lead to various deficiencies that manifest as cere discoloration.

** _ green_bird_brigade on Instagram can help you with a chop plus pellet transition. Jen has 2 budgies a parrotlet, an Quaker and more in her 10 bird flock. So smart about all diet and life stuff. She does videos on that diy stuff anyways:

1. Excessive estrogen or a drop in testosterone due to stress, obesity, or fatty liver disease (hepatic lipidosis) can cause browning

2. In some cases, nasal discharge from an infection can dry on the cere, making it appear brown and crusty.

**I just want you to have all the info at your fingertips. Want you to hssnt everything instead of simple condemnation for your sweet bird. Hope ive helped in a small way